T4TT posted:I am grateful the UP revived 4014. Will 4014 ever run without a diesel helper? It has been years since I saw the Challenger in StL but i don't recall 3985 having a helper...maybe it did. With our without help, the Big Boy is a sight to see and I look forward to doing just that.
She'll almost always have a diesel in the consist.
The three reasons as stated by Ed Dickens are:
1) Dynamic braking on long downgrade runs, to preserve the air brake shoes on the Heritage Fleet equipment.
2) To reduce fuel and water consumption by assisting in hauling the train as circumstances warrant.
3) For switching, turning and positioning the consist for display.
Also, although not explicitly stated, to guard against mechanical failure of the steam locomotive and tying up the railroad.
